[PATCH] parisc: Add checks to verify page alignment in cache

[Helge Deller <deller@gmx.de>]

functions
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Add checks to ensure that only page-aligned addresses are provided.

Signed-off-by: Helge Deller <deller@gmx.de>

diff --git a/arch/parisc/include/asm/cacheflush.h b/arch/parisc/include/asm/cacheflush.h
index 0bdee6724132..ff07c509e04b 100644
--- a/arch/parisc/include/asm/cacheflush.h
+++ b/arch/parisc/include/asm/cacheflush.h
@@ -15,6 +15,9 @@ DECLARE_STATIC_KEY_TRUE(parisc_has_cache);
 DECLARE_STATIC_KEY_TRUE(parisc_has_dcache);
 DECLARE_STATIC_KEY_TRUE(parisc_has_icache);

+#define PA_CHECK_PAGE_ALIGNED(addr) \
+	WARN_ON_ONCE((unsigned long)addr & ~PAGE_MASK)
+
 #define flush_cache_dup_mm(mm) flush_cache_mm(mm)

 void flush_user_icache_range_asm(unsigned long, unsigned long);
diff --git a/arch/parisc/kernel/cache.c b/arch/parisc/kernel/cache.c
index 1d3b8bc8a623..595968f708c3 100644
--- a/arch/parisc/kernel/cache.c
+++ b/arch/parisc/kernel/cache.c
@@ -317,6 +317,7 @@ __flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr,
 {
 	if (!static_branch_likely(&parisc_has_cache))
 		return;
+	PA_CHECK_PAGE_ALIGNED(vmaddr);
 	preempt_disable();
 	flush_dcache_page_asm(physaddr, vmaddr);
 	if (vma->vm_flags & VM_EXEC)
@@ -550,6 +551,7 @@ void flush_kernel_dcache_page_addr(const void *addr)
 {
 	unsigned long flags;

+	PA_CHECK_PAGE_ALIGNED(addr);
 	flush_kernel_dcache_page_asm(addr);
 	purge_tlb_start(flags);
 	pdtlb(SR_KERNEL, addr);
@@ -567,8 +569,10 @@ static void flush_cache_page_if_present(struct vm_area_struct *vma,
 	 * a non-access TLB miss. Hopefully, the page has already been
 	 * flushed.
 	 */
-	if (ptep && pte_needs_flush(*ptep))
+	if (ptep && pte_needs_flush(*ptep)) {
+		PA_CHECK_PAGE_ALIGNED(vmaddr);
 		flush_cache_page(vma, vmaddr, pfn);
+	}
 }

 void copy_user_highpage(struct page *to, struct page *from,
@@ -712,6 +716,7 @@ void flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr, unsigned
 {
 	if (WARN_ON(!pfn_valid(pfn)))
 		return;
+	PA_CHECK_PAGE_ALIGNED(vmaddr);
 	if (parisc_requires_coherency())
 		flush_user_cache_page(vma, vmaddr);
 	else